Subtract 30/9 from 25/21
1st number: 1 4/21, 2nd number: 3 3/9
25/21 - 30/9 is -15/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
25/21 = 25 × 3/21 × 3 = 75/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
30/9 = 30 × 7/9 × 7 = 210/63 - Subtract the two like fractions:
75/63 - 210/63 = 75 - 210/63 = -135/63 - After reducing the fraction, the answer is -15/7
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